This invention relates generally to soffit to attic vents or ventilation baffles for permitting the free flow of ventilation air between roof rafters.
In order to maintain the integrity of home attic insulation, it is necessary to ensure adequate air ventilation between the roofing boards and the attic insulation. If the roofing boards contacts the attic insulation, there is a possibility that the free flow of ventilation air will be restricted and the integrity of the insulating material will be degraded due to the build-up of condensation and ice. Over the years, various insulation vents and ventilation baffles have been developed to ensure a free flow of air between the roof insulation and the roof boards. These vents generally take the form of elongated troughs which are mounted between the roof rafters or trusses. A precut piece of insulating batting or a stop board is then placed between the wall plate and the troughs to prevent spillage of loose fill insulation into the soffit area. Quite often, this batting or stop board is installed improperly, leading to heat loss and or mouldy interior comers.
Several designs for ventilation baffles have been proposed which purport to eliminate or reduce the likelihood of attic insulation, particularly loose fill insulation, from falling into the soffit area. Two such devices are disclosed in U.S. Pat. No. 4,265,060 to Woodhams and U.S. Pat. No. 4,189,878 to Fitzgerald. Both of these structures have a downwardly extending wall at one end which contacts the upper wall plate. This downwardly extending wall prevents insulation from falling into the soffit area. While both the Woodhams and Fitzgerald devices may be effective, their structures make them very difficult to install from the inside of the home while maintaining both rafter to rafter and roofboard to wall plate adjustability. Furthermore, prior air vents may inadvertently act as vapour barriers between the insulation and the trough""s ventilation area, which may result in the build-up of ice or condensation on the surface of the insulation side of the vent. Therefore, there is a need for an effective soffit to attic which is inexpensive to manufacture, easy to install from the inside, and yet remains effective for both truss and stick frame applications.
The present invention is a ventilation baffle and stop for use in buildings having walls made of wall studs, wall plates mounted on top of the wall studs, said wall plates having a top surface and a front surface facing away from an interior of the building, a plurality of spaced apart roof rafters mounted on top of the top surface of the wall plates, and roof sheathing mounted on top of the roof rafters. The ventilation baffle made in accordance with the present invention includes a substantially rectangular sheet of stiff material having opposite first and second ends and opposite first and second side edges. The sheet has a first pair of longitudinally extending, parallel, fold lines respectively located close to the opposite side edges of the sheet, said first pair of fold lines dividing the sheet into a rectangular central portion and a first pair of elongated rectangular side edge portions on opposite sides of said central portion. The sheet also includes a second pair of longitudinally extending, parallel, fold lines respectively located between and extending parallel to, the first fold lines and the opposite side edges, said second pair of fold lines dividing the first pair of elongated rectangular side edge portions into a first pair of flange portions positioned adjacent the side edges and a first pair of spacer portions positioned adjacent the central portion. The first pair of elongated rectangular side edge portions are bendable upward relative to the central portion to form upstanding sides, the first pair of flange portions being bendable outwardly relative to the central portion to form tabs position able adjacent the opposing surfaces of a pair of adjacent roof rafters, said tabs being attachable to an inside surface of the roof sheeting mounted onto the roof rafters, said first pair of spacer portions separating the central portion of the sheet from the tabs and defining an air-flow passageway between the central portion and the roof sheeting. The sheet also has a transversely extending fold line located towards the first end and defining an outer rectangular end portion so that said rectangular end portion can be positioned adjacent to and above the top plate and can be bent downwardly relative to the central portion to define an outer downwardly extending end wall between the opposing surfaces of a pair of adjacent roof rafters and extending downwardly from said central portion substantially into contact with said top plate, said end wall being attachable to the plate.
Other features and advantages of the invention will be evident from the following detailed description when read in conjunction with the accompanying drawings which illustrate the invention.